Adhesive materials or filling materials are used for restorative treatment of teeth, bones, etc. Dental polymerizable compositions containing a polymerizable monomer, a polymerization initiator, a filler, etc., are generally used as such adhesive materials or filling materials. A dental polymerizable composition is used in the form of a cured product obtained by polymerizing a polymerizable monomer in the composition having been formed into a desired shape. Specifically, such dental polymerizable compositions are used in applications such as mobile tooth fixing materials, denture liners, dental cements, and dental self-adhesive composite resins. A mobile tooth fixing material is a material for fixing a loose tooth (mobile tooth) to the adjacent healthy teeth. A denture liner is a material for improving the adaptation of a denture used. A dental cement is a material used to bond a prosthesis (such as an inlay, a crown, a bridge, a denture, or an implant) to a missing portion of a tooth. When it is checked whether such a prosthesis functions properly in an oral cavity for a certain period of time, a temporary dental cement is used so that the prosthesis can be removed from a missing portion after the check. A dental self-adhesive composite resin is a material for filling a missing portion of a tooth.
A dental polymerizable composition must be easily formed into a desired shape when applied directly from a container. Specifically, the composition must be capable of being discharged from the container with less discharging force and being formed into a desired shape immediately after being discharged. On the other hand, a cured product obtained from the dental polymerizable composition thus formed is required to have surface gloss, stain resistance, etc.
A mobile tooth fixing material as a cured product is required to have shock absorbing capacity and adhesion to enamel when subjected to an external force. The cured product must have a flexural modulus within an appropriate range to increase its shock absorbing capacity. A denture liner as a cured product is required to have low surface hardness and high distortion resistance. A dental cement, particularly a temporary dental cement, as cured product, is required to have a flexural modulus within an appropriate range so that it can be removed. In terms of close adhesion to a missing portion of a tooth, a dental self-adhesive composite resin is required to reduce polymerization shrinkage stress during curing.
As dental polymerizable compositions that meet these requirements, those containing an elastomer have been known. For example, Patent Literature 1 has reported a dental polymerizable composition containing an acrylic block copolymer consisting of a polymethacrylic acid ester and a polyacrylic acid ester. There is, however, a demand for further improved dental polymerizable compositions that require less discharging force, reduce polymerization shrinkage stress during curing, and form a cured product having higher resistance to stain, distortion, etc.